Amazon said it's offering the promotion for up to four years. In cases like this, we can look at Prime as something of a loss leader for the company, with the idea being that a subscription to Prime encourages users to do more of their shopping through Amazon.

Those who want to qualify for the discount will be asked to apply and upload a photo of their Medicaid card.

Inc.is expanding its discounted Prime program, its latest salvo in a battle with Walmart Inc. for low-income shoppers.

"People that this opportunity are targeting are going to get that chance for the first time - and they may actually need it more".

The cheapest option for a typical Amazon Prime member is to pay $100 a year to renew their membership on an annual basis. Amazon already has a stranglehold on wealthy shoppers: More than 70% of upper-income households-with annual income over $112,000-had Amazon Prime memberships, according to one study. The Seattle retail giant previous year introduced that discounted rate for people who receive government food assistance and have a valid Electronic Benefits Transfer card.

Medicaid provides health insurance to millions of Americans, including low-income adults, children, the elderly and people with disabilities.